RESEARCH / Focused target
The complete A381737 Conjecture 2 recurrence
RELEASED FOUNDATIONS / PROPOSED CONNECTION
Research connections
All source anchors (1)
- D5/S3/Analytic/Polynomial/HermiteTieRecurrence.resultAbsent from this graph
Problem
The question
OEIS A381737 revision 28, by Mike Sheppard (2025), names the sequence:
Orders k of Hermite polynomials whose maximal coefficient in absolute value appears twice.
Its Formula field states:
Conjecture 2: a(n) = a(n-1) + 2a(n-2) - 2a(n-3) - a(n-4) + a(n-5).
The offset is 1,1. Let $H_k$ be the physicists Hermite polynomial represented
by HermiteSignedMode.physicistsHermite over the rationals. For every
natural order $k$ and exponent $j$, put
$$ M(k,j)\iff j\le k\ \land\ \forall i\le k,\quad |[x^i]H_k|\le |[x^j]H_k|. $$
Let $S$ consist of exactly the natural orders $k$ for which there are natural exponents $u<v$ such that, for every natural $j$, $M(k,j)$ holds if and only if $j=u$ or $j=v$. Thus exactly two distinct exponents attain the absolute maximum of the entire row $0,\ldots,k$, including parity-zero coefficients.
The complete assertion is that there exists $g:\mathbb Z\to\mathbb N$ satisfying all of the following:
- For every integer $n\ge1$, $g(n)>0$.
- For all integers $1\le n<m$, $g(n)<g(m)$.
- For every natural order $k$, including zero, $k\in S$ if and only if there is exactly one integer $n\ge1$ with $k=g(n)$.
- For every integer $n\ge6$,
$$ (g(n):\mathbb Z)=(g(n-1):\mathbb Z)+2(g(n-2):\mathbb Z) -2(g(n-3):\mathbb Z)-(g(n-4):\mathbb Z)+(g(n-5):\mathbb Z). $$
Every sequence value is cast separately to the integers before subtraction. The positive-index restriction of $g$ is the actual increasing exhaustive one-based enumeration of $S$. Its values at nonpositive indices impose no restriction on this event. There is no finite cutoff, eventual qualification, selected subfamily, signed maximum, probabilists normalization or recurrence-defined replacement sequence.
Motivation
Our foothold
The whole external Conjecture 2 event is preregistered at
https://github.com/the-omega-institute/trureturing/issues/25941#issuecomment-6593756660.
Its execution-clock reference is
https://github.com/the-omega-institute/trureturing/issues/25941#issuecomment-6594367458.
The original forecasts and clock remain those immutable source records.
The stronger frozen Conjecture 1 enumeration supplies the actual sequence;
its separate dossier is oeis-a381737-hermite-absolute-ties.
Gap
Missing bridges
A recurrence of an arbitrary sequence would not identify the source event. The needed bridge retains every qualifying polynomial order, positive index, and unique membership correspondence while transferring the frozen natural-indexed integer formula to a natural-valued enumeration indexed by positive integers. Finite source programs do not prove this universal event.
Route
Proposed approach
HermiteAbsoluteTieOrders.result supplies positivity, strict increase and
exhaustive unique positive indexing for the original predicate, with
$$ b(m)=2m(m+2)+(m+1)(-1)^{m+1}. $$
For positive integer $n$, use $g(n)=\operatorname{toNat}(b(n.\operatorname{toNat}))$.
Positivity makes the integer cast of this natural value equal to $b$.
Positive natural and positive integer indices correspond exactly, preserving
strict increase and unique exhaustion. At $t=n-5$, the existing quadratic
and alternating linear formula satisfies the displayed recurrence by power
expansion and polynomial normalization. The retained private
formula_recurrence helper is used by the public result on that live path.
No new classification of Hermite coefficient ties is required.
Falsifier
What would falsify this route
The complete event would fail if no total increasing exhaustive positive-index enumeration with unique indexing existed, or if its actual values violated the displayed recurrence at some integer $n\ge6$. A discrepancy must concern this actual enumeration of the full original coefficient rows. A prefix, other normalization or proxy sequence cannot decide the event.
Evidence
Evidence to collect
D5/S3/Analytic/Polynomial/HermiteTieRecurrence.result proves the entire
claim. The owning Scribe attaches a typed OpenProblemResolutionClaim
of kind Proved to this dossier. The canonical delivery has no corresponding
theory atom and uses deposit-uncovered for this GID.
The public result and its consumed private formula_recurrence helper
are both proof_shape: bind-only; escape_witness: none.
The admission basis is open-problem-resolution, with the external source
and preregistration above. The claim definition states the exact source
event. All declarations have utility: none: this is an unbounded mathematical
consequence, with no bounded enumeration, checker, numerical-premise reduction
or certified finite-instance delivery. The stronger frozen C1 supplier is
attributed; this resolution grants no automatic independent new-result or
KPI credit.
The author Reg mirror is
Reg/D5/S3/Analytic/Polynomial/HermiteTieRecurrence.lean.
Its source-family proofs compile, but the audit is declared_unresolved,
certificate null, diagnostic IE-C050 ClosedTruthReadout, reason
unclassified_form, rule source.observation_data.
The missing accepted source-observation reconstruction/binding certificate
is disclosed under the CLAUDE 3.9 linked-issue exception:
https://github.com/the-omega-institute/trureturing/issues/25957.
This is an unfinished audit, not declared_validated.
Triage
Scope assessment
The source classification is theorem. The resolution covers the complete
Conjecture 2 actual-enumeration recurrence. C1's separate dossier and
mathematical supplier retain their original scope. Conjecture 3 remains
outside this resolution.
What the settlement shows
Proved by D5/S3/Analytic/Polynomial/HermiteTieRecurrence.result: the stronger
C1 closed formula already forces C2 for the complete actual enumeration,
with no additional assumptions or finite index bound. Positivity permits
exact integer/natural transport; the quadratic and alternating linear
parts provide the recurrence mechanism. The proof settles this neighboring
question of C1 without another coefficient classification. It neither
changes C1's statement nor settles Conjecture 3. No additional general
recurrence theorem or new mathematical endpoint is claimed.
ASSUMED-UNVERIFIED
Unverified assumptions
The mapping from the source name, offset and conjecture to the explicit quantified event is a source-to-formal correspondence; Lean verifies the formal event, not OEIS prose. The checked repository, pinned Mathlib, selected Lean-ecosystem and source searches identified no prior whole named C2 settlement in their inspected scopes. These are bounded literature and reuse checks, not worldwide openness, originality or priority certification. Rooney's full text, the unidentified Dudeja-Hsu citation and broad citation tails remain uninspected. Source programs and finite agreement supply no universal proof. The unfinished Reg binding audit and the existing raw/scoped reader boundaries recorded in issues #15595 and #24733 remain disclosed; selected build success does not clear those boundaries or certify all CI.